The present invention relates to a lubrication oil feed device for an internal combustion engine and particularly to the ducts for feeding oil from a supply to units supported on the engine block.
In motor vehicles, particularly heavier vehicles such as trucks and buses, there is an increasing need to provide or coordinate the vehicle engine with additional units of different types. In this case, the additional units may belong to the engine, such as an injection pump or a turbocompressor unit, or they may be units driven by the engine, for example an air compressor in a compressed air system for brake operation, or they may be other equipment which interacts with the engine.
In the case of heavier trucks and buses in particular, the vehicle engine is often a diesel engine which operates on the basis of supercharging generated by means of a turbocompressor. Lock free braking systems are frequently also used in such vehicles, wherein the brakes are operated by a compressed air system. A common feature of these types of vehicles and engines is the need to be able to fit the equipment concerned and the units required for it on or close to the vehicle engine for drive and functional reasons. In a number of cases, the equipment and units also must be fitted with efficient lubricating oil systems. It is appropriate for these lubricating oil systems to be coordinated with the engine lubricating system. In practice, this is achieved by incorporating the lubricating system of the equipment/units respectively in the engine lubricating oil system.
According to the prior art, equipment/units of the type discussed above are mounted on a common supporting part which is securely fitted to the vehicle engine. The type of supporting part may, for example, be a supporting plate which is normally secured to the short side of the engine block adjacent to the clutch which is normally integral with the engine. This type of supporting plate is normally called a transmission plate. Lubricating oil is then normally fed to/from the equipment or units mounted on the transmission plate via external hoses or pipes which connect lubricating oil ducts of the equipment/units to lubricating oil ducts in the engine block. In this case, the connections between the ends of the hoses/pipes and equipment/units and the engine block respectively are normally made by means of nipples.
In order to avoid the need for such external hoses/pipes between the units/equipment and engine block altogether, or at least to minimize this requirement, solutions have also been developed where the external hose and pipe connections have been replaced by die cast or drilled ducts inside the transmission plate itself. This obviates the need for such hoses and pipes. But, the transmission plate must, on the other hand, be designed as a cast cover which, because of the space required for its internal ducts, must of necessity have a much greater thickness than a conventional transmission plate without internal ducts.
The disadvantages of such a cast cover provided with internal oil ducts are, among other things, that it has a large design thickness, it is expensive to manufacture, and it is very heavy.